This invention relates to pivoting vane hydraulic pumps and motors with vane timing.
U.S. patent Documents
Currently there are two basic types of pivoting vane pumps or motors. The first has the pivoting vane pivoting at one end of the vane and the other has the pivoting vane pivoting near its center. Historically both types produced variable volume outputs and have the pressurizing vanes sliding on the inner housing surface creating friction and wear. In addition, these pumps/motors have circular inner housings surfaces providing sealing at only one point.
Most pivoting vanes pivot between two vane stops that limit the rotation of the vane. When the vane is resting on the rotor and it is closed is the first vane stop. The second vane stop limits the vane rotation when the vane is pressurizing, i.e., it is open. Unless a specific vane stop is created the vane stop becomes the circular inner housing surface, creating wear and friction.
Accordingly, the main object and advantage of this invention is to create a pivoting vane pump or motor with vane stops that produce a constant volume output, at a given speed, and increased mechanical efficiency, by reducing friction, in a cost-effective way. A new pivoting vane with a new housing performs these objects and advantages. This pump/motor minimizes friction because the pressurizing vanes do not contact the chamber wall. In addition, the clearances on this pump decrease with increased pressures allowing for greater pressures. Further objects and advantages of my invention will become apparent from a consideration of the drawings and ensuing description.
In the drawings, closely related figures have the same number but different alphabetic suffixes. A description of the first suffix describes the other suffixes.
There is no unique size for the pump and usually measures in inches, but a pivoting vane motor for hydroelectric production may be 10-20 feet in diameter. The pump rotates counterclockwise.
U.S. Pat. No. 4,762,480 is for a rotary pump with the pivot at one end of the vane. The pump has a circular housing and “a plurality of vanes pivotally mounted on the periphery of the rotor having free ends in sliding sealing contact with said bore,” from the ABSTRACT lines 11-13, This pump uses the housing surface for a vane stop.
U.S. Pat. No. 4,846,638 is on a rotary fluid machine with pivoting vanes that is used as a compressor or a pump. This patent also has the vane pivoting near the center of the vane and a cam action that is in effect a vane stop. The cam action opens and closes the vanes and allows for wear at both ends of the vane to compensate for wear on each other. Even with the cam effect, they are using the housing surface for a vane stop as stated in SUMMARY OF THE INVENTION, paragraph 3, lines 11-13 “The vanes are, thus, designed and positioned to automatically self compensate for frictional wear on the vanes.”
U.S. Pat. No. 5,163,825 is for an air or hydraulic motor with a vane stop specifically designed as a vane stop. In the DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS, first paragraph, lines 7-9, “These forces bring the tips of the vanes into contact with the inner cylindrical wall of the housing 12.” The vanes wear away and create a clearance and the vane stop prevents the clearance from increasing.
U.S. Pat. No. 5,571,005 is for a hinged vane rotary pump that has the vane hinged near the center of the vane and a circular housing with the vanes riding on the housing surface. This patent has a vane stop for closed vanes but not an open vane and consequently rides of the housing surface. As stated in the ABSTRACT, lines 9-11, “Preferably, stops are provided to limit movement of the vanes after maximum wear has occurred.”
U.S. Pat. No. 6,939,117 B2 is for a rotary apparatus that is both a hydraulic pump and motor. The ABSTRACT states, lines 9-11 “the gates form a seal against surface (22), of outer housing (16) and a retracted position in which the gates (20) lie substantially against surface (24) of the housing (12).” Claim 24 states, “The machine according to claim 23, wherein each socket and each gate is provided with a first set of respective stop surfaces that come into mutual abutment when the gates swing to the sealing position from the retracted position.”
The arc of a opening arc 58 is tangent to the arc of big seal 64 and tangent to a line 72a, a line. The arc of a closing arc 60 is a mirror image, top to bottom, of the arc of opening arc 58. Line 72a is tangent to opening arc 58 and small seal 62. A line 72b is a mirror image of line 72a and is tangent to closing arc 60 and small seal 62. A groove 66a is approximately the same length, has the same center, but a slightly larger radius, as opening arc 58. A groove 66b is approximately the same length, and has the same center, with a larger radius, as closing arc 60. Groove 66b extends from about five degrees before the end of big seal 64 to a point near small seal 62 wherein vane 52a can close without trapping fluid.
One end of the arc of vane pivot 76a is tangent to the arc of close seal 74a. The other end of the arc of vane pivot 76a ends at the line of vane flat 82a. The other end of vane flat 82a ends at pressure seal 84a. The arc of vane pivot 76a is not continuous because of a pin holder 78a. Pin holder 78a is a cylindrical cut centered on the edge and approximately midway on the length of vane pivot 76a. A heel 80a occurs at the intersection of closed seal 74a and pressure seal 84a. When vane 52a opens or closes, it rides on heel 80a preserving closed seal 74a and pressure seal 84a.
When vane 52a reaches the position of vane 52b, the pressure/draw cycle is over. Vane 52b position has slid onto groove 66b. Groove 66b breaks the pressure seal and allows vane 52b to close without any pressure bias on one side. As the rotating vane 52b moves to the vane 52c position groove 66b allows vane 52b to close by allowing the fluid to escape. Groove 66a allows fluid to slide past vane 52a-c until the start of the pressure cycle.
Consequently only one vane 52a-c is pumping, for 120 degrees, at any time. When vane 52a-c looses pressure, the next vane 52a-c is in position to begin pressurizing and provides a constant output volume for pump 20.
Thus, the reader will see that the pivoting vane pump creates a highly efficient pump or motor. This efficiency stems from vane 52a-c not touching the big seal 64 when pressurizing fluid and having no pressure bias when opening or closing. Another advantage is that with increased pressure there will be a slight flexing of the vane, which will reduce vane/wall clearances even further.
The advantage of this invention is vane timing where only one vane produces pressure for 120 degrees and consists of the following three improvements.
Consequently vane timing produces a pump or motor that operates at a given volume and pressure while minimizing friction. This contrast to earlier pivoting vane pumps that were continuously producing pressure that had variable volume and pressure outputs. Earlier pivoting vane pumps also had the vane sliding on the pressurizing surface that created more friction with increasing pressure.
The pivoting vane pump is the only positive displacement pump in the world that accommodates backpressure. Besides hydraulic pumps and motors, a multi-chambered pivoting vane pump makes a transmission for bicycles, tricycles, etc. The pivoting vane also makes gas compressors, for compressing air, etc. The pivoting vane motor also works as a water turbine for hydroelectric production.
While my description contains many specifications, these should not be construed as limitations on the scope of the invention, but rather as exemplification of one preferred embodiment thereof.
Accordingly, the scope of the invention should be determined not by the embodiments illustrated, but by the appended claims and their legal equivalents.
A Provisional Patent Application was filed on Mar. 5, 2009, Application No. 61/209,405, Confirmation No. 9218 by Thomas P. Kadaja.
Number | Date | Country | |
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61209405 | Mar 2009 | US |